Advantages and Disadvantages of Prefabricated Houses

Prefabricated houses have advantages such as fast construction speed and low cost, but also have disadvantages such as poor seismic performance and fragile connection points.

Advantages of Prefabricated Houses

1. Fast Construction Speed: Components are prefabricated in the factory in advance and assembled on-site, which is 60-70% faster than traditional house building. For example, in rural areas of Henan, the main structure of a prefabricated house can be assembled in as little as two hours.
2. Low Cost: The main structure is about 30% cheaper than that of a brick house, allowing ordinary families to save tens of thousands of yuan. Factory-based unified production reduces material waste, and large-scale production reduces material costs by 20%-40% and labor costs by about 60%. However, after the price increase of cement, prefabricated houses are only 5% cheaper than traditional buildings, and transportation costs to remote areas can account for 5% of the total cost.
3. Environmental Protection: The recycling rate of construction waste is high, and carbon emissions are reduced. Some projects have even received international certifications.
4. Good Quality: Factory prefabrication has small errors. The houses can pass a 7-magnitude earthquake simulation test, have less overall settlement than ordinary houses, and have higher concrete strength than traditional construction. After adopting the reinforced concrete integral pouring process, the seismic performance can be upgraded to an 8-magnitude standard, and the service life can be extended to 70 years.
5. Low Post-Maintenance Costs: The post-maintenance costs are 40% lower than those of traditional houses, but the annual maintenance costs will increase by 1,500 - 3,000 yuan after 20 years.
6. Improvement through New Technologies: The sound insulation and heat insulation effects have been improved through sandwich insulation design.

Disadvantages of Prefabricated Houses

1. Poor Seismic Performance: The overall integrity is poor. In the event of an earthquake or shaking, the floor slabs and walls are prone to separation, and the collapse is sudden without crack warnings or deformation buffers.
2. Fragile Connection Points: The connections between prefabricated panels and walls, and between panels and panels are simple. When the foundation settles or the walls crack, the panels are prone to misalignment and loosening.
3. Material Problems: Some prefabricated houses use substandard materials to cut costs, such as thin steel bars and non-compliant concrete grades, resulting in high brittleness and easy fracture.
4. Prone to Ground Water Seepage: The building components are poured with cement without steel bar reinforcement. Over time, the cement components are prone to cracking, and there are large gaps between the assembled components, resulting in poor water seepage resistance.
5. Poor Sound Insulation and Heat Insulation Effects: It is stuffy and unbearable in summer and cold inside in winter. The sound insulation effect is also poor, with a 20-decibel difference in sound insulation, and noises from upstairs can be clearly heard.
6. Difficult to Modify the Structure: Load-bearing walls cannot be removed, and the house structure cannot be changed. Moreover, the house type design may lack humanization.
7. Short Service Life: The service life of some prefabricated houses is 30 - 40 years, which is a gap compared to the 70-year service life of current commercial houses.
8. Quality Risks: There is a 7% probability of foundation settlement or wall cracks within 5 years due to non-standard construction, and construction in low-temperature environments is more prone to problems.